Many homeowners—particularly those that live in older houses—are not sure where their tank and field are buried in relation to the house. It is most important that you locate the tank because eventually it will need service. First find the pumpout and observation ports. Look for a surface or underground manhole, or a riser pipe that stands just above the soil surface. You can also also use a narrow steel rod about 1/8″ in diameter to gently probe the soil for the tank and distribution box. If you can’t find the tank, hire a professional to locate it for you.
Once you find the tank, try to locate the disposal field, which usually fans from a distribution box. Then diagram both of these features on a map that you keep in a handy place. Be aware, however, that finding the laterals can be hard—so much so that in some cases even septic contractors have difficulty locating all the components. They can use a dye test to reveal the location of failures, but this method may not pinpoint the actual sites of the laterals. Most important, pump out your tank on a regular basis. When the tank is not cleaned, solids build up until they spill into the disposal field, where they block the fiow of liquid. The frequency depends on the size of the tank and the number of people it services. Tanks should be inspected at least once every two years to determine the rate of sludge (solids on the bottom of the tank) and scum buildup. With ordinary use and care, a septic tank usually requires cleaning every three to five years (more if you use a sink-mounted garbage disposal unit). However, in many cases septic tanks can be operated for up to five years if properly maintained.
Depending on the size of the tank and your location, plan on spending about $200 for each pumpout. Before you contract with the service technician, ask him to check the tank baffles for possible damage. While the tank is open, the technician can also run some water from a hose into the distribution box to get an indication of how well the leach field is functioning. One caution: toxic gases build up in septic tanks, so never allow anyone to go into the tank. You should also exercise caution when simply peering in the tank.
Don’t plant trees or bushes near your disposal field. Roots can grow 30′ to 40′ from the base of a tree and rupture or dislodge the distribution box, connecting pipes, and laterals. Grass is the best vegetative cover for the disposal field. Also, don’t drive vehicles or heavy equipment over the disposal field. Watch for excessive water from inside the house. It will overload the tank, causing solids to rise to the top and clog the laterals. In the disposal field, excessive water can result in hydraulic overloading that reduces soil infiltration. One way to reduce the amount of water entering the system is to install water-saving toilets and showerheads. Try to distribute dishwashing and laundry times throughout the week rather than at one or two sessions. Fix leaking toilets and faucets, and don’t connect sump pumps to the septic system.